Live GMAT classes with Target Test Prep start Nov 21 and Nov 22. First class free.

See classes
Target Test Prep · GMAT

Choose how you want to prepare

Learn live with an expert or move at your own pace. Every option includes the complete TTP study system.

Newsweek Readers’ Choice Awards 2026 winner: Target Test Prep, #1 Test Prep

Target Test Prep was voted #1 Best Test Prep in the 2026 Newsweek Readers’ Choice™ Awards.

★★★★★5.0563 reviews
GMATLiveTeachStarts Nov 22
Josh Braslow, Target Test Prep GMAT expert
LIVE ONLINE CLASSES

Get Ready for GMAT Test Day Faster with Live Online Classes

with Josh Braslow, 20+ years in test prep

Nov 22 · Josh Braslow
Sun · 9:30 AM to 12:30 PM ET
Included
40 hours of live online classes + 6 months of TTP OnDemand
  • Attend the first class for free
  • Every class is recorded, so you never fall behind
View classes & enroll
Limited seats availableTarget Test Prep
EALiveTeachOnDemandStart anytime
EXECUTIVE ASSESSMENT

Target Test Prep EA OnDemand

Self-paced EA prep. Study on your schedule.

EXECUTIVE ASSESSMENT

with

165+ EA score guarantee
$05-day trial no automatic billing
Schedule
Included
40 hours of live online classes plus six months of access to the complete TTP EA OnDemand course.
  • 165+ EA Score Guarantee
  • 4,100+ Quant, Verbal, and Integrated Reasoning practice questions
  • 400+ hours of in-depth video lessons
  • 3,000+ step-by-step video solutions
View EA class & enroll Start free 5-day trial
Limited cohort · enrollment openTrial includes full course accessTarget Test Prep
GMATOnDemandStart anytime
SELF-PACED MASTERCLASS

Target Test Prep GMAT OnDemand

Complete access from day one. Study on your schedule.

715+ score guarantee
$0to start then $127/mo
  • Personalized study plan and analytics
  • Thousands of lessons and practice questions
Start free 5-day trial
Read 563 reviewsTarget Test Prep

Measure of external angle.

Expert replies
Post new topic Post Reply
Subscribe topic
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 107
Joined: Tue Oct 07, 2008 10:09 pm
GMAT Score:710
by sumitkhurana » Thu Jan 29, 2009 6:45 am
What is the measure of an external angle of
the triangle ABC?
(1) One of the internal angles measures 72
degrees.
(2) The triangle ABC is an isosceles triangle.
Top
Join the discussion
Source: — Data Sufficiency |
User avatar
Site Admin
Posts: 2567
Joined: Thu Jan 01, 2009 10:05 amFollowed by: 550 members
Thanked: 712 times
GMAT Score:770

by DanaJ » Thu Jan 29, 2009 8:12 am
1. is sufficient because the external angle corresponding to the angle with a measure of 72 degrees is (180 - 72) = 108.
2. is insufficient because just knowing that the triangle is isosceles is not enough. We would need a numeric value for one of its angles to answer the question.

So I'd go with A.
Top
Join the discussion
Senior | Next Rank: 100 Posts
Posts: 38
Joined: Tue Jan 27, 2009 10:24 am

by sanjay_dce » Thu Jan 29, 2009 8:20 am
IMHO E is the ans Danaj has mistakenly assumed which exterior angle is being asked, its not necesarrily connected with the interior angle given in stmt2.

hence E
Top
Join the discussion
User avatar
Site Admin
Posts: 2567
Joined: Thu Jan 01, 2009 10:05 amFollowed by: 550 members
Thanked: 712 times
GMAT Score:770

by DanaJ » Thu Jan 29, 2009 8:35 am
I suppose you're right.... I don't really know... I guess my explanation would be ok if we had been asked the measure of any of the exterior angles... Not a particular angle. It's all about wording.
Top
Join the discussion
User avatar
GMAT Instructor
Posts: 3224
Joined: Tue Jan 08, 2008 2:40 pmFollowed by: 614 members
Location: Toronto
Thanked: 1710 times
GMAT Score:800

by Stuart@KaplanGMAT » Thu Jan 29, 2009 12:41 pm
DanaJ wrote:I suppose you're right.... I don't really know... I guess my explanation would be ok if we had been asked the measure of any of the exterior angles... Not a particular angle. It's all about wording.
I agree.

The question asks ""What is the measure of an external angle of
the triangle ABC?"

From statement (1), we can certainly determine the meansure of AN external angle of the triangle. Therefore, (1) is sufficient on its own.

"Is this what the question writer intended to ask" is a completely different issue and speaks to the reliability of the source. Whenever one posts a question, one should post the source as well so we know how seriously to take it.
Image

Stuart Kovinsky | Kaplan GMAT Faculty | Toronto

Kaplan Exclusive: The Official Test Day Experience | Ready to Take a Free Practice Test? | Kaplan/Beat the GMAT Member Discount
BTG100 for $100 off a full course
Top
Join the discussion
Senior | Next Rank: 100 Posts
Posts: 38
Joined: Tue Jan 27, 2009 10:24 am

by sanjay_dce » Fri Jan 30, 2009 10:56 pm
DanaJ wrote:I suppose you're right.... I don't really know... I guess my explanation would be ok if we had been asked the measure of any of the exterior angles... Not a particular angle. It's all about wording.[/quote

Looks like the question is incomplete, otherwise (with the information provided out here)DanaJ u r correct, I take my words back :oops:
Top
Join the discussion